8152537: aarch64: Make use of CBZ and CBNZ when comparing unsigned values with zero.
Summary: aarch64: c2 make use of CBZ and CBNZ when comparing unsigned values with zero.
Reviewed-by: aph
--- a/hotspot/src/cpu/aarch64/vm/aarch64.ad Tue Mar 29 10:07:54 2016 +0000
+++ b/hotspot/src/cpu/aarch64/vm/aarch64.ad Wed Mar 23 18:00:46 2016 +0800
@@ -14242,6 +14242,48 @@
ins_pipe(pipe_cmp_branch);
%}
+instruct cmpUI_imm0_branch(cmpOpU cmp, iRegIorL2I op1, immI0 op2, label labl, rFlagsRegU cr) %{
+ match(If cmp (CmpU op1 op2));
+ predicate(n->in(1)->as_Bool()->_test._test == BoolTest::ne
+ || n->in(1)->as_Bool()->_test._test == BoolTest::eq
+ || n->in(1)->as_Bool()->_test._test == BoolTest::gt
+ || n->in(1)->as_Bool()->_test._test == BoolTest::le);
+ effect(USE labl);
+
+ ins_cost(BRANCH_COST);
+ format %{ "cbw$cmp $op1, $labl" %}
+ ins_encode %{
+ Label* L = $labl$$label;
+ Assembler::Condition cond = (Assembler::Condition)$cmp$$cmpcode;
+ if (cond == Assembler::EQ || cond == Assembler::LS)
+ __ cbzw($op1$$Register, *L);
+ else
+ __ cbnzw($op1$$Register, *L);
+ %}
+ ins_pipe(pipe_cmp_branch);
+%}
+
+instruct cmpUL_imm0_branch(cmpOpU cmp, iRegL op1, immL0 op2, label labl, rFlagsRegU cr) %{
+ match(If cmp (CmpU op1 op2));
+ predicate(n->in(1)->as_Bool()->_test._test == BoolTest::ne
+ || n->in(1)->as_Bool()->_test._test == BoolTest::eq
+ || n->in(1)->as_Bool()->_test._test == BoolTest::gt
+ || n->in(1)->as_Bool()->_test._test == BoolTest::le);
+ effect(USE labl);
+
+ ins_cost(BRANCH_COST);
+ format %{ "cb$cmp $op1, $labl" %}
+ ins_encode %{
+ Label* L = $labl$$label;
+ Assembler::Condition cond = (Assembler::Condition)$cmp$$cmpcode;
+ if (cond == Assembler::EQ || cond == Assembler::LS)
+ __ cbz($op1$$Register, *L);
+ else
+ __ cbnz($op1$$Register, *L);
+ %}
+ ins_pipe(pipe_cmp_branch);
+%}
+
// Test bit and Branch
// Patterns for short (< 32KiB) variants